It’s TIME for a New Environmental Modelling Framework

The Invisible Modelling Environment (TIME) is a new environmental modelling framework being developed within the Catchment Modelling Toolkit project in the CRC for Catchment Hydrology. TIME differs from existing modelling frameworks in a number of ways, particularly in its use of metadata to describe and manage models as well as the flexibility given to model developers to `pick and choose' the components of TIME relevant for a given project. Functionality that is embedded as an immutable `core' layer in other frameworks is included in applications under TIME on an as-needed basis using optional, interchangeable components. This flexibility extends to components that manage data and models, recognising that one approach does not necessarily fit all applications. TIME includes a number of small framelets supporting extension in key areas such as data representation and visualisation. All fundamental data types, such as rasters and time series, are defined within the data framelet, which supports the definition of new, compatible data types. The visualisation framelet allows the definition of `layers', each providing a visual representation of some type of data, such as rasters or polygons. Multiple layers can be placed on a single `view', such as overlaying a polygonal map on a raster. Views can be surrounded by `decorators' such as axis and titles, each of which can be combined independently. TIME includes a number of tools, which operate generically on models, including an automatic user interface generator and various model optimisation tools. TIME is developed on the Microsoft.NET platform and supports the development of models in a variety of languages, including Visual Basic.NET, Fortran 95.NET, C# and Visual J#. TIME is currently being used to develop a range of modelling applications, including a library of rainfall runoff models and a model supporting assessment of stream ecosystem health under various flow scenarios.